invented Jyy John Peuji, Esq., LeuoisJiam. 



127 



grown. In Jig. 21. a 

 is the front glass, near- 

 ly upright, and con- 

 sequently well adapted 

 for winter forcing, when 

 the sun is low, and will 

 strike it nearly at a 

 right angle; b is the 

 path of boards under 

 which sea-kale, chic- 



cory roots, &c., in pots y o o 

 might be forced; c, '^S^l^^B 

 the horizontal glass 



over the border ; and d, the gratings to the drains. The di- 

 rection of the current of air is shown by the arrows. Fig. 22. 

 shows part of the ground 

 plan, in which e e are the 

 drains, J" J" the situation of 

 the gratings, g the hot- 

 water pipes, and h the air- 

 tube. A thermometer, and 

 a hygrometer acting by gra- 

 vity, might be hung inside ^/j Yi 

 the front glass, and inspect- 

 ed by walking along the 

 boarded path. When prun- 

 ing or watering was re- 

 quired, the warmest mo- 

 ments of a fine day should 

 be chosen, and the sashes opened one by one for a few minutes. 

 Fumigation by tobacco might be performed when necessary, by 

 burning the tobacco over the hot-water pipes ; and it is almost 

 unnecessary to observe that the atmospheric moisture might be 

 increased to any desirable extent, by throwing down water among 

 these pipes, so as to cover the bottom of the drains. 



To prove the rapidity of the circulation, it is only necessary to 

 throw a piece of burning paper among the pipes, or a little rose 

 water or fragrant oil over them, when in a few seconds the smoke 

 or the fragrance will be perceived over the front path. To 

 make this construction and arrangement economical, shutters 

 of boards, or of hurdles covered with bark, reeds, or straw, 

 should be adopted both for the front and horizontal glass. 



About the end of the last century, an attempt was made in the 

 neighbourhood of Bristol by Dr. Pritchard and others, and re- 

 vived again by a Lincolnshire gentleman, to enclose a large space, 

 cover it with glass, and heat the interior to the temperature of 

 Madeira, as a substitute for that climate to invalids : the plan did 



